Process for the utilization of ruminant animal methane emissions

ABSTRACT

A process for the utilization of the methane produced by enteric fermentation, specifically to a process that utilizes methane produced by ruminant animals through enteric fermentation as a source of carbon and/or energy for the directed production of methane-based goods or processes is provided.

RELATED APPLICATIONS

This application is a continuation-in-part of patent application Ser.No. 10/687,272, filed Oct. 15, 2003 now U.S. Pat. No. 6,982,161 andclaims the benefit of Provisional Application No. 60/603,857, filed Aug.24, 2004, all incorporated by reference herein.

BACKGROUND OF THE INVENTION

1. Field of Invention

This invention relates generally to processes for the reduction ofruminant animal methane emissions, specifically to a process for theutilization of ruminant animal methane emissions as a source of energy.

2. Description of the Related Art

Methane emissions from ruminant animals account for about twenty percentof total global methane emissions, and atmospheric methane accounts forabout twenty percent of planetary warming. In addition to theenvironmentally destructive effects of ruminant animal methaneemissions, such emissions represent wasted energy, as a significantpercentage of the food ruminant animals eat is lost as methane.Accordingly, there have been significant efforts in the past to reduceruminant animal methane emissions.

Ruminant animal methane emissions, or, more specifically, entericfermentation methane emissions, originate in the four-stomach digestivetract common to all ruminant animals, which includes the rumen, a largeforestomach connected to the four-stomach digestive tract. The rumencontains a host of digestive enzymes, fungi, bacterium, and protozoa,and the bulk of digestion, as well as methane production via entericfermentation, takes place here. Not surprisingly, all prior efforts toreduce enteric fermentation methane emissions from ruminant animals,which include dairy cows, beef cattle, sheep, goats, water buffalo, andcamels, have focused on modifications associated with the rumen ordigestive tract.

Past modification efforts have included: vaccines designed to limitmethanogenic, or methane-producing, microorganisms in the rumen ordigestive tract; feed reformulations designed to alter the chemical ormicrobial environment of the rumen or digestive tract to limit methaneproduction; feed reformulations designed to decrease the amount ofmethane-producing foods entering the rumen or digestive tract; andselective breeding aimed at encouraging the reproductive success ofruminant animals which produce relatively low amounts of methane,presumably as a result of factors associated with the rumen or digestivetract.

While most of these prior efforts have had some success in reducingenteric fermentation emissions, none has been shown to completely, oreven significantly, eliminate ruminant animal methane production. Sincelimited success in reducing methane production concurrently limits theeconomic benefits of using methane-reducing vaccines, feed formulations,or selective breeding, ruminant animal owners have generally been averseor reluctant to employ these methods. Thus, as the ruminant animalpopulation continues to grow in accord with ever-increasing worldwidedemand and methane reduction efforts fail to reduce emissions in anysignificant way, enteric fermentation methane emissions remain asignificant source of both environmental degradation and wasted energy.

Prior to the applicants' discovery, no methods were known to reduceruminant animal methane emissions by using such methane as a source ofenergy in energy consumption systems maintained outside of the digestivetracts of ruminant animals. In the past, all ruminant animal methanereduction processes have focused on limiting ruminant animal methaneproduction rather than reducing overall atmospheric emissions through asystem of methane utilization. Thus, it is one feature of severalembodiments of the present invention that ruminant methane emissions arereduced through the utilization of ruminant animal methane as a sourceof energy.

Methane-utilizing, or methanotrophic, microorganisms are well known inthe microbiology art for their capacity to grow and reproduce usingmethane as a source of carbon and/or energy. Methanotrophicmicroorganisms, specifically bacteria, have even been employed to reduceruminant animal methane emissions by being placed directly in the rumenor digestive tract of ruminant animals and subsequently limitingproduction at its source. They have never, though, been employed in amicrobiological growth system. They have also never been employed in amicrobiological growth and harvest system that reduces ruminant animalenteric fermentation methane emissions while concurrently providing ameans for harvesting products of microorganism growth, such asmicroorganism biomass. Methods for the utilization or consumption ofmethane gas as a source of feedstock fuel, including fuel used for theproduction heat, electricity, liquid natural gas, compressed naturalgas, chemicals, industrial feedstock, and a range of other goods, arewell known for their capacity to use methane as a source of energy.However, none of these methods has ever been employed to reduce entericfermentation methane by using such methane as a source of energy for theinduction of methane-based processes or for the production ofelectricity, heat, and/or other methane-based products.

Prior to the applicants' discovery, no methods were known to utilizeruminant animal methane emissions as a source of energy. Morespecifically, the connection between enteric fermentation methaneemissions from ruminant animals and the directed production ofmethane-based goods or methane-driven processes through the utilizationof enteric fermentation methane as a source of carbon and/or energy hadever been made. At least two major factors likely inhibited such aconnection. First, it is not a well-known fact that, under certainconditions, certain ruminant animals produce enough methane to makemethane-consumption systems such as electricity, heat, or microorganismproduction platforms technically and/or economically feasible. Second,ruminant animal methane emissions are not considered a viable source ofcarbon or energy because they are considered low-volume,non-concentrated, and, thus, unusable methane emissions. While up toninety-five percent of enteric fermentation methane emissions exit thedigestive tracts of ruminant animals as exhalation, most continue toregard such emissions as components of low-volume, diffuse, unusableflatulence. No methods are known to capture and/or consolidate entericfermentation methane emissions in a way that would convert them into astate suitable for use as a fuel stream for the production ofmethane-based goods or processes. Enteric fermentation methaneoriginates as diffuse emissions, and no methods are known to convertsuch emissions into a usable form. For these and other reasons, ruminantanimal methane emissions have never been considered as a viable sourceenergy, and the connection between enteric fermentation methaneemissions and methane-driven process and goods production has neveroccurred.

Mechanical ventilation systems are well known in the livestock andagricultural science art for their capacity to draw, push, or pull airthrough a fully or partially enclosed ruminant animal holding, feeding,or enclosure area. The main function of mechanical ventilation systems,including tunnel ventilation systems and other ventilation systems, isto provide air flow or air exchange in order to maintain or improve thehealth of ruminant animals in a fully or partially enclosed holding orfeeding area. It is also well known in the livestock and agriculturalscience art that some mechanical ventilation systems, particularlytunnel ventilation systems, have the capacity to force all or some ofthe air inside a fully or partially enclosed ruminant animal holding orfeeding area through specific vents or fans. The outflow air coming outof ventilation fans have even been forced, directed, or led into mulch,compost, and/or other platforms designed to limit or reduce outflow airodor or dust emissions. Prior to the applicants' discovery, though, suchventilation systems used in conjunction with enclosure structures hadnever been considered as means to enable the capture, consolidation, andutilization of ruminant animal methane emissions as a source of energy.It is one feature of several embodiments of the present invention thatanimal enclosure structures and/or ventilation systems are applied asmeans to capture, consolidate, direct, and/or convey ruminant animalmethane emissions to enable the use of such emissions as a source ofenergy. Prior to the applicants' discovery, ventilation systems and/orenclosure structures had never been used to capture ruminant animalenteric fermentation methane emissions, nor had such emissions ever beenused to grow bacteria in a bioreactor optionally equipped with means toharvest any of the microbial products associated with bioreactoractivity, particularly microbial biomass. Similarly, prior to theapplicants' discovery, ventilation systems and/or enclosure structureshad never been used to capture enteric fermentation methane forutilization by a methane-consumption system such as a reverse-flowreactor or microturbine. The utilization of air conveyance systems tocapture enteric fermentation methane for use as a source of carbonand/or energy overcomes a range of practical problems associated with asystem for capturing methane emissions from the nose and/or mouth of aruminant animal using on-animal apparatuses such as bioreactors ormicroturbines, including animal mobility problems and reactor sizerequirements for optimal methane conversion. The straightforwardutilization of structures, means, and systems that are well known and/orcommonly used also overcomes a range of prior emissions captureproblems, including practicability, palatability, and viability. One ofskill in the art will understand that currently available and otherventilation systems can be used in accordance with embodiments of theinvention.

No previous methods were known to reduce ruminant animal methaneemissions by using such methane as a source of energy. Consequently,ruminant animal methane emissions remain a significant source ofenvironmental degradation.

Several embodiments of the present invention relate to a process for theutilization of the methane produced by ruminant animals through entericfermentation as a novel source of energy.

Embodiments of the invention have several surprising and unexpectedadvantages over the prior art, some of which are surprising andunexpected. One or more of these advantages are present in certainpreferred embodiments of the present invention. Further objects andadvantages will become apparent from the ensuing description.

SUMMARY OF THE INVENTION

In accordance with several embodiments of the invention, a processwherein the methane produced through ruminant animal entericfermentation is utilized as a source of carbon and/or energy for theinduction of a methane-driven process and/or for the production ofmethane-derived materials, such as methane-utilizing microorganisms,heat, and/or electricity. In one embodiment of a process carried out inaccordance with the invention, this process may be accomplished by a)enclosing one or more ruminant animals in an enclosure means, such as abarn, and b) contacting air contained in such an enclosure means,including the enteric fermentation methane contained therein, with amethane-consumption system, whereby enteric fermentation methaneemissions are utilized as a novel source of carbon and/or energy for theinduction of a methane-based process and/or for the production ofmethane-based products, such as heat, electricity, and/ormethane-utilizing microorganisms.

In another embodiment, a method for producing methane-based products orprocesses in a confined apparatus comprising using the entericfermentation methane produced by one or more ruminant animals as asource of carbon and/or energy for the production of methane-basedproducts or processes is provided. In one embodiment, this methodcomprises: (a) providing one or more ruminant animals, (b) providingenteric fermentation-derived methane gas that has been emitted by theanimals, including air containing the methane, (c) providing means tocapture, consolidate, and/or direct the methane, including providing anenclosure means to enclose the animals, the air, and the methane andproviding an air conveyor means to direct the air and the methane, (d)providing a methane-consumption means which can use the methane as asource of carbon and/or energy in a methane-based process and/or for theproduction of methane-based goods, and (e) contacting the methane withthe methane-consumption means to cause the methane-consumption means tooxidize, consume, and/or otherwise utilize the methane for the operationof a methane-based process or for the production of one or moremethane-based products, including methane-utilizing microorganisms,heat, and/or electricity.

In another embodiment, this method comprises: (a) providing one or moreruminant animals, (b) providing an enclosure means to fully or partiallyenclose and/or otherwise encapsulate the animals, (c) providing entericfermentation-derived methane gas that has been emitted by the animals,(d) providing enclosure air that has been combined with the methane inthe enclosure means, (e) providing a methane-consumption means which canuse the methane as a source of carbon and/or energy for the induction ofa methane-based process or the production of methane-based goods, (f)providing a means for contacting the air containing the methane with themethane-consumption means, including a means for the conveying the airto the methane-consumption means whereby the methane can be utilized asa source of carbon and/or energy by the methane-consumption means, (g)mutually-contacting and/or exposing the methane and themethane-consumption means to cause the methane-consumption means tooxidize, consume, and/or otherwise utilize the methane for the inductionof one or more methane-based processes or for the production of one ormore methane-based products, including methane-utilizing microorganisms,heat, and/or electricity, whereby the methane produced by the animals isutilized for the sustained production of the process and/or the productsin a specified apparatus.

As discussed previously, methane is an environmentally-destructivematerial and previously unusable source of energy, which, according toone preferred embodiment of the invention, is used to produce a usefulend-product that can be used or sold for use, providing an economicincentive to a ruminant animal methane emissions reduction effort. Inone embodiment, the end-product is heat. In another embodiment, theend-product is fuel. In yet another embodiment, the end-product iselectricity. In yet another embodiment, the end-product is another formof energy. In a further embodiment, the end-product is the culture ofmicro-organisms.

In one embodiment, the enclosure means includes any means by which theanimals are fully or partially enclosed or encapsulated. The enclosuremeans includes, but is not limited to, a barn, greenhouse, and/or anyother suitable enclosures or housing.

In one embodiment, the term “air” as used herein shall be given itsordinary meaning, and shall include all airborne and gaseous componentsof air that has been contacted with the methane in the enclosure means,including the methane emitted by the animals contained within theenclosure means, as well as ammonia gas, dust, and/or other airbornematerials that may be present in the air.

In one embodiment, methane-consumption means includes any means by whichthe methane is oxidized, consumed, and/or otherwise used as a form ofcarbon and/or energy. Methane-consumption means includes, but is notlimited to, methane-utilizing microorganisms, fuel cells, turbines,reverse-flow reactors, engines, microturbines, and/or any othermethane-consumption means.

In one embodiment, the ammonia contained within the air is contactedwith liquid water and converted into ammonium and used as a source ofnitrogen by the methane-utilizing microorganisms.

In one embodiment, the dust and/or other airborne material within theenclosed air is reduced prior to or in the course of using the methanewithin the air as a source of carbon and/or energy.

In one embodiment, the methane within the air is used by themethane-consumption means in conjunction with alternative sources ofmethane, such as coal mine methane, landfill gas methane, natural gasmethane, manure digester methane, wastewater treatment methane, and/orother sources of methane.

In one embodiment, a method for producing methane-based products orprocesses using the enteric fermentation methane produced by one or moreruminant animals as a source of carbon and/or energy, comprising: (a)providing one or more ruminant animals, (b) providing entericfermentation-derived methane gas that has been emitted by said animals,(c) providing an enclosure to fully or partially enclose and/orotherwise encapsulate said animals, (d) providing enclosure air that hasbeen combined with said methane in said enclosure, (e) providing amethane-consumer which can use said methane as a source of carbon and/orenergy for the operation of a methane-based process and/or for theproduction of methane-based goods, (f) contacting said methane-consumerwith said enclosure air containing said methane to cause saidmethane-consumer to oxidize, consume, and/or otherwise utilize saidmethane for the operation of a methane-based process or for theproduction of one or more methane-based products, including but notlimited to methane-utilizing microorganisms, heat, and/or electricity.

In one embodiment, an air conveyor is provided to direct, move, and/orotherwise convey enclosure air, wherein can be used to contact said airwith said methane-consumer.

In one embodiment, the methane-consumer is one or more of the following:methane-utilizing microorganisms, fuel cells, microturbines, turbines,methane-based engines, and/or reverse-flow reactors.

In one embodiment, the enclosure is erected, modified, and or used toenclose the animals and to make the methane available for use by themethane-consumer.

In one embodiment, the air comprises air, dust, methane, ammonia, gases,flies, particulate matter, and/or other airborne matter fully orpartially contained by the enclosure.

In one embodiment, the methane and the methane-consumer are contactedfor the purpose of reducing emissions of the methane and/or the dust,the ammonia, the particulate matter, and/or other components of the air.

In one embodiment, the methane is used to generate electricity and/orheat.

In one embodiment, the methane is contacted with the methane-consumer toreduce methane emissions and/or simultaneously create harvestableproducts.

In one embodiment, a method for producing methane-based products orprocesses using the enteric fermentation methane produced by one or moreruminant animals as a source of carbon and/or energy, comprisingcollecting air containing the methane and conveying the air to amethane-consumption system that will utilize the methane within theconveyed air for the production of one or more methane-based processesand/or products.

In one embodiment, the methane-consumption system is any system that canutilize the air as a feedstock fuel stream for the production of amethane-based process or product, wherein the system may be amethane-utilizing microorganism growth system, a microturbine system, areverse-flow reactor system, and/or any other methane-driven system.

In one embodiment, the enclosure is provided and utilized to collectsaid air containing said methane.

In some embodiments, one of skill in the art will appreciate that one ormore of the above steps described herein is modified or omitted.Further, the steps need not be conducted in the order set forth herein.

Besides the objects and advantages described herein, some advantages ofseveral embodiments of the present invention include:

(a) to provide a process that converts previously harmful emissions inthe form of the methane produced by ruminant animals through entericfermentation into useful goods;

(b) to provide a process which overcomes previously insurmountableproblems in the continuous collection and utilization of ruminant animalmethane emissions;

(c) to provide a process which provides a direct economic incentive forruminant animal methane emission reductions;

(d) to provide a process which reduces ruminant animal entericfermentation methane emissions without altering the chemical ormicrobial make-up of the digestive tract of ruminant animals;

(e) to provide a process which reduces ruminant animal methane emissionswithout requiring ruminant animals to alter their normal/naturalbehavior patterns, including sleeping and nutrient-consumption;

(f) to provide a process which reduces ruminant animal methane emissionswithout requiring feed reformulations, selective breeding activities, orchemical or microbial modifications to the digestive systems of ruminantanimals;

(g) to provide a process which can be integrated into ruminant animalownership operations;

(h) to provide a process which improves living conditions for ruminantanimals,

(h) to provide a process which reduces dust, ammonia, and/or odorproblems associated with ruminant animal operations,

(i) to provide a process which reduces enteric fermentation methaneemissions through a system of methane utilization, and/or

(j) to provide a process which converts an environmentally destructivegreenhouse gas into a harvestable and economically valuable end-product,such as microorganism biomass, heat, and/or electricity.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side perspective view of an apparatus used to carry out aprocess in accordance with on embodiment of the invention. In theillustration, the apparatus is self-contained and maintained entirely onthe body of a ruminant animal. FIGS. 2A, 2B, 3A, and 3B describe thisapparatus in greater detail.

FIG. 2A is a top cross-sectional view of one of two parts of theapparatus depicted in FIG. 1. The part of the apparatus illustrated isthe permanent exhalation conveyance structure that is attached to thebody of a ruminant animal.

FIG. 2B is a side perspective view of one of two parts of the apparatusdepicted in FIG. 1. The part of the apparatus illustrated is thepermanent exhalation conveyance structure that is attached to the bodyof a ruminant animal.

FIG. 3A is a side cross-sectional view of one of two parts of theapparatus depicted in FIG. 1. The part of the apparatus illustrated isthe removable microorganism containment capsule that is inserted intothe permanent exhalation conveyance structure.

FIG. 3B is a side perspective view of one of two parts of the apparatusdepicted in FIG. 1. The part of the apparatus illustrated is theremovable microorganism containment capsule that is inserted into thepermanent exhalation conveyance structure.

FIG. 4 is a schematic of a preferred embodiment of a process carried outin accordance with one embodiment of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

While this invention is susceptible to embodiments in many differentforms, there is shown in the drawings and will herein be described indetail preferred methods of carrying out a process in accordance withembodiments of the invention with the understanding that the presentdisclosure is to be considered as an exemplification of the principlesof the invention and is not intended to limit the broad aspect of theinvention to the embodiment illustrated.

As used herein, the terms “ruminant animal methane”, “entericfermentation methane”, and “ruminant animal enteric fermentationmethane” shall be given their ordinary meaning and shall also refer toany methane produced and emitted by one or more ruminant animals as aresult of processes associated with enteric fermentation. An averageadult dairy cow will emit approximately 150 kg of enteric fermentationmethane per year, while beef cattle will each produce about two-thirdsof that volume, or 100 kg per year. Methane emitted by ruminant animalsis a particularly important greenhouse gas, since on a ton-to-ton basisit has 21 to 23 times the heat-trapping capacity of carbon dioxide.

The term “consolidation means” shall be given its ordinary meaning andshall also refer to any means by which enclosure air is unified,mutually-directed, and/or otherwise consolidated for conveyance. In onepreferred embodiment, a consolidation means comprises an air-tightducting tube running from an air outlet to a mutual-exposure means, asdescribed below, wherein enclosure air is directed out of an enclosedarea, through a consolidation means, and into a mutual-exposure means.In another preferred embodiment, a consolidation means comprisesmultiple ducting tubes connected to air outlets and situated toconsolidate outflowing enclosure air into a single ducting tube thatultimately leads as one or more air streams into a methane-consumptionsystem.

The term “ventilation means” shall be given its ordinary meaning andshall also refer to any means by which air, gases, and/or other airbornematerial is mechanically forced, pushed, pulled, drawn, moved, conveyed,or otherwise directed into, through, and/or out of a spatial areaenclosed by an enclosure means. In one preferred embodiment, well-knownventilation fans, such as rotating ventilation fans and/or tunnelventilation fans, operate in a well-known barn ventilation process,whereby air may be drawn into a barn through one or more open spaces ina barn wall and directed out of a barn through ventilation fans. In onepreferred embodiment, an enclosure means is provided with ventilationmeans, wherein air is moved into and out of an enclosure means at anoverall combined rate of 10 cubic feet per minute per dairy cow. In onepreferred embodiment, means for the cooling of barn-enclosed air arealso provided in order to ensure animal well-being in an enclosed area.A number of air-cooling means are well known, such as cooling pads,water sprayers, and air conditioning units.

The term “ruminant animal” shall be given its ordinary meaning and shallalso refer to one or more ruminant animals, including, as in onepreferred embodiment, a dairy or beef cow.

The terms “enclosure means” and “means for enclosure” shall be giventheir ordinary meaning and shall also refer to any means by which someor all of the space in which one or more ruminant animals exist ispartially or fully confined, isolated, encapsulated, and/or enclosed,such as a barn or greenhouse structure. In one preferred embodiment, abarn with a specified air inlet, such as a window, and a specified airoutlet, such as a window housing a ventilation fan, encloses a ruminantanimal (e.g., dairy cow).

The term “air inlet” shall be given its ordinary meaning and shall alsorefer to any location where air, gas, and/or other airborne materialenters into an area or chamber fully or partially enclosed by anenclosure means. In one preferred embodiment, an air inlet comprises aspatial opening, such as a window, in the wall of an enclosure means.

The term “air outlet” shall be given its ordinary meaning and shall alsorefer to any location where air, gas, and/or other airborne materialexits out an area or chamber fully or partially enclosed by an enclosuremeans. In one preferred embodiment, an air outlet comprises a spatialopening housing a ventilation means located in the wall of an enclosuremeans.

The term “enclosure air” shall be given its ordinary meaning and shallalso refer to the air, gases, and/or other airborne material that havebeen mixed with enteric fermentation methane in the space fully orpartially enclosed by an enclosure means, including enteric fermentationmethane, ammonia, dust, and/or other airborne material contained withinan enclosure means containing a ruminant animal.

Methane-utilizing microorganisms represent one embodiment of a“methane-consumption system” or “methane consumption means”, that is,e.g., a mechanical, chemical, and/or biological system that utilizesenteric fermentation methane as a source of carbon and/or energy. Theterm “methane-utilizing microorganisms” shall be given its ordinarymeaning and shall also refer to any microorganism, naturally-occurringor genetically-engineered, that utilizes methane, including entericfermentation methane, as a source of carbon and/or energy. The term“methane-utilizing microorganisms” also refers to the mixture ofmethane-utilizing and non-methane-utilizing microorganisms that arecollectively associated with the growth of methane-utilizingmicroorganisms. In one embodiment, this microorganisms mixture includesone or more of the following: Methylococcus capsulatus, Alcaligenesacidovorans, Bacillus firmus, and Bacillus brevis. In one embodiment, amixture of these microorganisms is used because among other advantagesthis mixture is known to promote the long-term growth of Methylococcuscapsulatus. The term “methane-utilizing microorganisms” also includesany methanotrophic organisms and organisms that use or “take-up”methane. Methane-utilizing microorganisms may be confined in amicroorganism holding tank containing methane-utilizing microorganismsand a microorganism growth-culture medium. They may also be present in abiofiltration system containing methane-utilizing microorganisms whereinmicroorganisms either are or are not attached to a microorganism supportsubstrate and are continuously or intermittently contacted with amicroorganism growth-culture medium. They may also be used in abioreactor containing methane-utilizing microorganisms and amicroorganism growth-culture medium wherein the growth-culture medium isin liquid, foam, solid, semi-solid, or any other suitable form andmethane-utilizing microorganisms are naturally-occurring and/orgenetically engineered and may or may not have been selectively insertedas part of a pre-determined microbial consortium. While the use ofspecified microorganism consortium may provide some benefits, anon-specified and naturally-equilibrating consortium of one or moremicroorganisms may also be employed. Typical examples ofmethane-utilizing microorganisms useful in several embodiments of thepresent invention include, but are not limited to, bacteria and yeast.

Suitable yeasts include species from the genera Candida, Hansenula,Torulopsis, Saccharomyces, Pichia, 1-Debaryomyces, Lipomyces,Cryptococcus, Nematospora, and Brettanomyces. The preferred generainclude Candida, Hansenula, Torulopsis, Pichia, and Saccharomyces.Examples of suitable species include: Candida boidinii, Candidamycoderma, Candida utilis, Candida stellatoidea, Candida robusta,Candida claussenii, Candida rugosa, Brettanomyces petrophilium,Hansenula minuta, Hansenula saturnus, Hansenula californica, Hansenulamrakii, Hansenula silvicola, Hansenula polymorpha, Hansenulawickerhamii, Hansenula capsulata, Hansenula glucozyma, Hansenulahenricii, Hansenula nonfermentans, Hansenula philodendra, Torulopsiscandida, Torulopsis bolmii, Torulopsis versatilis, Torulopsis glabrata,Torulopsis molishiana, Torulopsis nemodendra, Torulopsis nitratophila,Torulopsis pinus, Pichia farinosa, Pichia polymorpha, Pichiamembranaefaciens, Pichia pinus, Pichia pastoris, Pichia trehalophila,Saccharomyces cerevisiae, Saccharomyces fragilis, Saccharomyces rosei,Saccharomyces acidifaciens, Saccharomyces elegans, Saccharomyces rouxii,Saccharomyces lactis, and/or Saccharomyces fractum.

Suitable bacteria include species from the genera Bacillus,Mycobacterium, Actinomyces, Nocardia, Pseudomonas, Methanomonas,Protaminobacter, Methylococcus, Arthrobacter, Methylomonas,Brevibacterium, Acetobacter, Methylomonas, Brevibacterium, Acetobacter,Micrococcus, Rhodopseudomonas, Corynebacterium, Rhodopseudomonas,Microbacterium, Achromobacter, Methylobacter, Methylosinus, andMethylocystis. Preferred genera include Bacillus, Pseudomonas,Protaminobacter, Micrococcus, Arthrobacter and/or Corynebacterium.Examples of suitable species include: Bacillus subtilus, Bacilluscereus, Bacillus aureus, Bacillus acidi, Bacillus urici, Bacilluscoagulans, Bacillus mycoides, Bacillus circulans, Bacillus megaterium,Bacillus licheniformis, Pseudomonas ligustri, Pseudomonas orvilla,Pseudomonas methanica, Pseudomonas fluorescens, Pseudomonas aeruginosa,Pseudomonas oleovorans, Pseudomonas putida, Pseudomonas boreopolis,Pseudomonas pyocyanea, Pseudomonas methylphilus, Pseudomonas brevis,Pseudomonas acidovorans, Pseudomonas methanoloxidans, Pseudomonasaerogenes, Protaminobacter ruber, Corynebacterium simplex,Corynebacterium hydrocarbooxydans, Corynebacterium alkanum,Corynebacterium oleophilus, Corynebacterium hydrocarboclastus,Corynebacterium glutamicum, Corynebacterium viscosus, Corynebacteriumdioxydans, Corynebacterium alkanum, Micrococcus cerificans, Micrococcusrhodius, Arthrobacter rufescens, Arthrobacter parafficum, Arthrobactercitreus, Methanomonas methanica, Methanomonas methanooxidans,Methylomonas agile, Methylomonas albus, Methylomonas rubrum,Methylomonas methanolica, Mycobacterium rhodochrous, Mycobacteriumphlei, Mycobacterium brevicale, Nocardia salmonicolor, Nocardia minimus,Nocardia corallina, Nocardia butanica, Rhodopseudomonas capsulatus,Microbacterium ammoniaphilum, Archromobacter coagulans, Brevibacteriumbutanicum, Brevibacterium roseum, Brevibacterium flavum, Brevibacteriumlactofermentum, Brevibacterium paraffinolyticum, Brevibacteriumketoglutamicum, and/or Brevibacterium insectiphilium.

The term “microorganism growth-culture medium” shall be given itsordinary meaning and shall also refer to any medium promoting the growthof microorganisms. It shall also refer to any substrate, aside frommethane, which microorganisms oxidize or otherwise break down. It shallalso refer to any substrate or material that concentrates methane,preferentially sequesters methane, “traps” methane, increases thesolubility and/or availability of methane, and/or otherwise enables theenhanced breakdown, oxidation, and/or utilization of methane bymicroorganisms. The term “microorganism growth-culture medium” includes,but is not limited to, any substrate and/or microorganism immobilizationmeans, such as liquid, semi-liquid, gas, particulate, ceramic, foam,plastic, alginate gel, methanol-enriched, copper-enriched, clay,nutrient, or other appropriate growth-culture medium. In one preferredembodiment, this growth culture medium comprises aqueous solutioncontaining water, nitrogen, ammonium, trace minerals, and otherwell-known microorganism growth-culture medium components necessary forthe growth and reproduction of methane-utilizing bacteria. In anotherpreferred embodiment, this growth culture medium comprises amicroorganism immobilization means, such as organic or inorganicparticles, on which a liquid or semi-liquid mineral medium solution iscontinuously or periodically contacted and on which microorganisms areattached. In another preferred embodiment, this growth-culture mediumcomprises waste organic materials, which methane-utilizingmicroorganisms may or may not break down to produce a byproduct oforganic materials that may or may not be useful. In another preferredembodiment, this growth-culture medium comprises a liquid foamsubstrate. In yet another preferred embodiment, this growth-culturemedium is mixed with various materials which methane-utilizingmicroorganisms may or may not convert to more desirable materials.Examples of various materials include, but are not limited to, toluene,trichloroethylene (TCE), propylene, and agricultural byproduct materialswhich microorganisms may preferentially breakdown or oxidize.

In one embodiment of the present invention, the method of the subjectinvention involves conveying enteric fermentation methane to anapparatus situated entirely on the body of a ruminant animal whichmutually-exposes methane-utilizing microorganisms, enteric fermentationmethane, and a microorganism growth-culture medium, causingmethane-utilizing microorganisms to grow using enteric fermentationmethane as a source of carbon and/or energy. Preferred embodiments ofthe invention are described below and illustrated by FIGS. 1, 2, and 3.

FIG. 1 is a side perspective view of an apparatus used to carry out aprocess in accordance with the invention. In this illustration, all ofthe means necessary for carrying out a process in accordance with theinvention are maintained and situated entirely on the body of ruminantanimal, including means for conveying ruminant animal exhalation, andthe exhalation methane therein, to a means for mutually-exposing entericfermentation methane, methane-utilizing microorganisms, and amicroorganism growth-culture medium, as well as a means for harvestingthe product of methane-utilizing microorganism growth.

In FIG. 1, exhalation collection tubes 15 a and 15 b are situated one oneither side of the head of ruminant animal 14. Tubes 15 a and 15 b areheld in place by stationary head harness 16 and lead up to the nostrilsof ruminant animal 14. Tubes 15 a and 15 b run from the nostrils ofruminant animal 14 to where they both converge into exhalationcollection tube convergence T-pipe 18. T-pipe 18 connects to exhalationinflow tube 19, which leads into permanent exhalation conveyancestructure 20. Structure 20 is described in further detail by FIGS. 2Aand 2B. Structure 20 is held in place on the back of ruminant animal 14by stabilizing leg straps 17 a, 17 b, 17 c, and 17 d, as illustrated.

FIG. 2A is a top cross-sectional view of structure 20, and FIG. 2B is aside perspective view of structure 20. Tube 19 passes through air pumphousing front wall 29 and leads into exhalation flow pipe chamber 43.Inside chamber 43, tube 19 connects to inflow pump chamber tube 21,which leads through chamber 43, through air pump housing middle wall 30,and into diaphragm-enclosed chamber 23. Where tube 21 opens into chamber23 is inflow one-way flap sphincter 22, which, being a one-way flap,allows air to travel into chamber 23, but does not allow air to travelfrom chamber 23 into tube 21.

Chamber 23 is enclosed by rubber diaphragm 44. The open end of diaphragm44 is attached to wall 30 so that an air-tight seal is made, and chamber23 is formed. Diaphragm pump plunger 31 is inserted through and intodiaphragm 44 on the side of diaphragm 44 farthest from wall 30. Plunger31 extends out of diaphragm 44 to where it is joined perpendicularly torotational gear tooth 32, which is attached to rotational gear 33. Gear33 is mounted on motor axle 36, which leads into direct-currentrotational motor 34. Motor 34 is located inside exhalation motor pumpingchamber 45. Positive motor electrical terminal 46 is connected topermanent structure positive conduction plate 37 by positive electricalconduction wire 35. Negative motor electrical terminal 47 is connectedto permanent structure negative conduction plate 38 by negativeelectrical conduction wire 48. Plate 37 and plate 38 are mounted on airpump housing back wall 27 with portions of each plate protruding throughand outside of wall 27. Connected to the end of plate 37 on the endfarthest from chamber 45 is positive conduction continuation spring 39.Connected to the end of permanent structure negative conduction plate 38on the end farthest from chamber 45 is negative continuation spring 40.Structurally, an electric current can now flow from spring 39 toterminal 46 as well as from spring 40 to terminal 47.

Returning to chamber 23, outflow one-way flap sphincter 24 leads outfrom chamber 23 and into outflow pump chamber tube 25. Sphincter 24allows air to travel out of chamber 23, but it does not allow air totravel from tube 25 into chamber 23. Tube 25 runs from chamber 23,through wall 30, and through chamber 43 to where it finally connectswith outflow insertion needle 26. Needle 26 runs from the inside ofchamber 43, protrudes through wall 27, and extends beyond wall 27directly away from tube 19. Needle 26 is open on the end farthest fromtube 25.

Half-cylindrical shell 42 is attached to wall 27. The orientation ofshell 42 is depicted in FIG. 2B. Running the length of shell 42 isinlaid guidance groove 41. As will be described later, groove 41 has thepurpose of guiding removable microorganism containment capsule 99 intocorrect orientation with needle 26, spring 39, and spring 40. Capsule 99is described in greater detail in FIGS. 3A and 3B.

FIG. 3A and FIG. 3B depict capsule 99. Specifically, FIG. 3A is a sidecross-sectional view of capsule 99, and FIG. 3B is a side perspectiveview of capsule 99. Structure 20 is designed to support and feedruminant animal exhalation (and the methane contained therein) intocapsule 99. Designed accordingly, capsule 99 is described in threeparts: threaded inflow attachment pipe 60, threaded outflow attachmentpipe 62, and microorganism growth capsule pipe 80. Capsule 99, as awhole, consists of each of these three pieces connected together, aswill be described.

Pipe 80 is threaded on the outer side of both ends and containsmethane-utilizing microorganisms 92 and microorganism growth-culturemedium 93. In the present embodiment, 5 grams of Methylococcuscapsulatus, methane-utilizing microorganisms which can be obtained froma number of biological supply depots (including Chang Bioscience,located at 125 Cambon Drive #6H, San Francisco, Calif. 94132) are placedin an aqueous microorganism growth-culture medium containing ammonium,nitrogen, and mineral salts.

Attached to one end of pipe 80 is pipe 60. Attached on the other end ofpipe 80 is pipe 62. Pipe 60 houses D-size battery 75, which is situatedbetween removable capsule positive electrical conduction terminal 70,removable capsule negative electrical conduction plate 74, and inflowattachment pipe inner wall 76. Plate 74 rests against wall 76 and sitsadjacent to battery 75. Terminal 70 sits adjacent to battery 75 andprotrudes through the front side of pipe 60. Similarly, terminal 71protrudes through the front side of pipe 60 from the inside of pipe 60.Capsule negative electrical conduction wire 49 runs from terminal 71 toplate 74. Running from the outer edge of the front side of pipe 60,passing through wall 76, and extending beyond wall 76 into pipe 80 isair dispersion capillary tube 72. Tube 72 is a solid tube except for theportion extending into pipe 80, which contains tiny capillary holes inits walls that allow air to pass out of tube 72 but do not allow medium93 to pass into tube 72. Tube 72 is open at the end meeting the outeredge of the front side of pipe 60, and closed at its opposite end.Attached to the outside of pipe 60 is inflow guidance ridge 89, a solidpiece of material which will eventually fit into groove 41 illustratedin FIG. 2A and FIG. 2B.

Attached to pipe 80 on the end opposite pipe 60 is pipe 62. Pipe 62 isan elbow-shaped pipe that allows air to escape after it has passedthrough the small holes in the walls of tube 72. Pipe 62 is a hollowpiece of piece of pipe at the end where it is connected to pipe 80,though, at its other end, pipe 62 is a solid piece of pipe. Wire meshgrating 61 is located inside pipe 62 at the border of where pipe 62turns from hollow to solid. Still inside of pipe 62, adjacent to grating61 in the solid portion of pipe 62, leak prevention holes 63 a and 63 bare drilled through the solid piece of pipe 62. Inside of hole 63 a areplug balls 64 a and 64 b. Inside of hole 63 b are plug balls 64 c and 64d. Balls 64 a, 64 b, 64 c, and 64 d are rubber balls which can float onthe surface of medium 93. Holes 63 a and 63 b are partially blocked atboth the ends farthest and the ends closest to the hollow portion ofpipe 62. Holes 63 a and 63 b are partially blocked by grating 61 at theend closest to the hollow portion of pipe 62. While the diameters ofholes 63 a and 63 b are constant throughout, the diameters decrease atthe ends farthest from the hollow portion of pipe 62 such that a singleball (64 a or 64 c) cannot pass through that end. Similar to ridge 89,outflow guidance ridge 90, which is able to slide into groove 41, islocated on the outside of pipe 62.

The following is a description of one method by which an apparatus isused to carry out a process in accordance with one embodiment of theinvention.

First, structure 20 is situated on the back of ruminant animal 14 usingstraps 17 a, 17 b, 17 c, and 17 d. Next, harness 16 is attached to thehead of ruminant animal 14, and tubes 15 a and 15 b are connected toharness 16 such that tubes 15 a and 15 b lead from T-pipe 18 up to thenostrils of ruminant animal 14.

Second, capsule 99 is placed into shell 42 of structure 20. This isaccomplished by inserting ridge 89 and ridge 90 on capsule 99 intogroove 41 inlaid in shell 42 of structure 20. With capsule 99 alignedwith structure 20, capsule 99 is slid towards wall 27 up to the pointwhere needle 26 is inserted into tube 72, and spring 39 and spring 40are placed, respectively, into contact with terminal 70 and terminal 71.With terminal 70 and terminal 71 placed into contact with spring 39 andspring 40, respectively, an electrical current now runs from battery 75in capsule 99 to motor 34 in structure 20. Specifically, a positiveelectrical current runs from battery 75, through terminal 70, throughspring 39, through plate 37, though wire 35, to terminal 46. A negativeelectrical current runs from battery 75, through plate 74, through wire49, through terminal 71, through spring 40, through plate 38, throughwire 48, to terminal 47.

With an electrical current running from battery 75 to motor 34, axle 36on motor 34 begins to rotate rapidly. As axle 36 rotates, gear 33 andgear tooth 32 also rotate rapidly, which in turn causes plunger 31 torapidly push and pull diaphragm 44. With diaphragm 44 oscillatingtowards and away from wall 30, the motion of diaphragm 44 causes air toflow from tubes 15 a and 15 b, into chamber 23, and into needle 26. Toexpand, air is pulled through tubes 15 a and 15 b, through T-pipe 18,through tube 19, through tube 21, past sphincter 22, through chamber 23,past sphincter 24, through tube 25, and into needle 26.

With capsule 99 inserted, as described above, into structure 20, air nowtravels from needle 26 into tube 72. Since tube 72 is blocked at the endlocated in pipe 80 and since air cannot travel from tube 72 back intochamber 23, air is forced out through the tiny holes which exist in thewalls of tube 72. To reiterate a detail mentioned above, tiny holesexist in the walls of tube 72 only where tube 72 extends into pipe 80.The result is that air is conveyed from needle 26, through tube 72, andinto pipe 80. Eventually, with no other means of escape, the air insidepipe 80 flows into the hollow portion of pipe 62, past grating 61, intoholes 63 a and 63 b, past plug balls 64 a, 64 b, 64 c, and 64 d, out ofholes 63 a and 63 b.

The result of this conveyance of air is that as ruminant animal 14exhales, this exhalation, as well as exhalation methane therein, isconveyed and directed into tubes 15 a and 15 b, which are situated justabove the nostrils of ruminant animal 14. Exhalation methane now travelsthrough tubes 15 a and 15 b to needle 26. With capsule 99 inserted, asdescribed above, into structure 20, exhalation methane of ruminantanimal 14 travels through needle 26 into pipe 80.

Pipe 80 contains microorganisms 92 and medium 93, and when exhalationmethane is conveyed into pipe 80, microorganisms 92 grow and reproduceusing this exhalation methane as a source of carbon and/or energy. Putdifferently, exhalation methane, microorganisms 92, and medium 93 aremutually-exposed in pipe 80. Thus, as more exhalation methane fromruminant animal 14 is exposed to microorganisms 92 in medium 93,microorganisms 92 grow and reproduce using exhalation methane as asource of carbon and/or energy. All excess gases, including waste carbondioxide and waste exhalation methane, exit capsule 99 as describedabove.

Although medium 93 is an aqueous medium, holes 63 a and 63 b, balls 64a, 64 b, 64 c, and 64 d, and grating 61 act together to prevent medium93 from spilling or escaping out of capsule 99. Specifically, since plugballs 64 a, 64 b, 64 c, and 64 d are designed to float on the surface ofmedium 93, if medium 93 travels past grating 61 and moves into holes 63a and/or 63 b, balls 64 a and 64 c will plug the small-diameter end ofholes 63 a and 63 b, respectively, before the aqueous medium 93 can passout of capsule 99.

The process continues when, after a certain amount of time (in thisembodiment approximately 7 days) it is determined that microorganisms 92within capsule 99 are no longer growing at optimal rates or have stoppedgrowing completely, and capsule 99 is removed from structure 20. Themicroorganism growth process is re-started and continued simply byreplacing previously-used capsule 99 with a new apparatus structurallyidentical to capsule 99 containing new methane-utilizing microorganismsand a new microorganism growth-culture medium. The process may also becontinued by re-using capsule 99 and, after removing all or most ofmicroorganisms 92 and medium 93, filling it with new microorganismgrowth-culture medium and an optimal number of new or previously usedmethane-utilizing microorganisms. In such a manner, exhalation methaneis continually used as a source of carbon and/or energy for the growthand harvesting of methane-utilizing microorganisms.

Finally, microorganisms 92, having been grown in capsule 99 usingexhalation methane as a source of carbon and/or energy, are removed fromcapsule 99 and harvested as useful biomass. (Methylococcus capsulatushas a biomass which consists of about seventy percent protein byweight). Such biomass can be processed and sold as a nutritionalfoodstuff or converted into other useful products, such as adhesives orcosmetics.

In one preferred embodiment, as detailed by FIG. 4, “mutual-exposuremeans” shall be given its ordinary meaning and shall also refer to anyapparatus housing, holding, or containing a methane-consumption systemsuch as microorganisms, fuel cells, or microturbines. In one embodiment,this apparatus comprises a holding tank containing methane-utilizingmicroorganisms and a microorganism growth-culture medium. In anotherembodiment, this apparatus comprises the materials housing and/orsupporting the operation of a reverse-flow reactor, an engine, a fuelcell, and/or a microturbine. In another embodiment, this means comprisesa temperature-controlled, stainless-steel cylindrical bioreactorapparatus containing, holding, or enclosing methanotrophic microorganismgrowth-culture medium and methane-utilizing microorganisms, into whichenclosure air, including ammonia and ruminant animal methane, is fed,conveyed, or directed, which subsequently allows microorganisms to growand reproduce utilizing ruminant animal methane as a source of carbonand/or energy for growth. In another embodiment, the growth of random,non-specified, genetically-engineered, pre-determined, and/ornon-pre-determined methane-utilizing microorganisms in such a bioreactormay be used to lower the concentration of ammonia in enclosure air. Inanother embodiment, means are provided to trap or capture dust and otherairborne matter in the enclosure air such that any or all of such matterdoes not actually contact a methane-consumption means, such asmethane-utilizing microorganisms or a methane-driven microturbine,reverse-flow reactor, or fuel cell. In this way, a mutual-exposure meansmay be used not only to carry out methane-driven processes, but also tolower the dust, ammonia, and/or airborne matter contents in enclosureair.

Embodiments of the subject invention pertain to the utilization of theenteric fermentation methane produced by ruminant animals for theproduction of methane-based goods. More particularly, embodiments of thepresent invention pertain to the process of utilizing ruminant animalenteric fermentation methane emissions in which the method comprises:(a) providing one or more ruminant animals, (b) providing entericfermentation-derived methane gas that has been emitted by the animals,including air containing said methane, (c) providing means to capture,consolidate, and/or direct the methane, including an enclosure means toenclose the animals, the air, and the methane contained in the air, and,preferentially, a ventilation means to direct the air, (d) providing amethane-consumption means which can use the methane as a source ofcarbon and/or energy for the induction of a methane-based process and/orfor the production of methane-based goods, and (e) contacting themethane with the methane-consumption means to cause themethane-consumption means to oxidize, consume, and/or otherwise utilizethe methane for the operation of a methane-based process or for theproduction of one or more methane-based products, includingmethane-utilizing microorganisms, heat, and/or electricity. Anotherembodiment of the invention pertains to the process wherein: a) one moreruminant animals are fully or partially enclosed by a well-knownenclosure means, such as a barn, and b) air contained in an ruminantanimal enclosure means, including the enteric fermentation methanecontained therein, is further directed and exposed to amethane-consumption system, whereby enteric fermentation methane is usedas a novel source of carbon and/or energy for the production of heat,electricity, or, as in one preferred embodiment, methane-utilizingmicroorganisms.

In one preferred embodiment, the method of the subject inventioninvolves contacting enteric fermentation methane contained withinenclosed barn air with a microbiological methane-consumption system,wherein enteric fermentation methane, methane-utilizing microorganisms,and a microorganism growth-culture medium are mutually-exposed, causingmethane-utilizing microorganisms to grow using enteric fermentationmethane as a source of carbon and/or energy.

FIG. 4 is a flow chart of a process carried out in accordance with theinvention. In the schematic, ruminant animal 114 is situated inenclosure means 115, whereby ruminant animal 114 is substantiallyenclosed, isolated, and contained by and in enclosure means 115. In onepreferred embodiment, enclosure means 115 includes a barn with foursidewalls and a roof.

Enclosure means 115 contains enclosure air 120. Enclosure means 115 isequipped with air inlet 116 and air outlet 117, through which air,gases, and other airborne materials are substantially confined to enterand exit enclosure means 115, respectively. In one preferred embodiment,air inlet 116 consists of a spatial opening, such as a window, in a sidewall of enclosure means 115, and air outlet 117 consists of a spatialopening housing ventilation means 113, through which air, gases, andother airborne material exit out of inside enclosure means 115. In onepreferred embodiment, ventilation means 113 consists of a well-knownventilation fan that is used to pull air into enclosure means 115through air inlet 116 and convey air out of enclosure means 115 throughair outlet 117. Consolidation means 112 is a duct that directs enclosureair 120 coming out of air outlet 117 in such a way that it can becontacted with confined methane-utilizing microorganisms 121. In theembodiment depicted, mutual-exposure means 119 is a holding tankcontaining a methane-consumption means, embodied as methane-utilizingmicroorganisms 121, and microorganism growth-culture medium 122. In theembodiment depicted, methane-utilizing microorganisms 121 are present ingrowth-culture medium 122 at a concentration of 20 grams ofmicroorganisms per liter of medium, and consist of methane-utilizingmicroorganisms such as Methylococcus capsulatus that can be obtainedfrom any number of well known biological supply depots (including ChangBioscience, located at 125 Cambon Drive #6H, San Francisco, Calif.94132). Growth-culture medium 122, as herein embodied, is an aqueousmedium containing suitable ammonium, mineral salts, and other well-knowngrowth-culture components, which support the growth of methane-utilizingmicroorganisms 121.

The following is a description of one method by which to carry out aprocess in accordance with one embodiment of the invention. First,ruminant animal 114 is enclosed by enclosure means 115, and ruminantanimal emits methane gas into enclosure air 120 through processesassociated with enteric fermentation. Next, through the force ofventilation means 113, air is conveyed into enclosure means 115 throughair inlet 116, through enclosure means 115, and out of enclosure means115 through air outlet 117. Enclosure air 120 containing entericfermentation methane is next conveyed out of air outlet 117, throughconsolidation means 112 to be contacted with methane utilizingmicroorganisms 121 in mutual-exposure means 119 through the forcecreated by ventilation means 113. Inside mutual-exposure means 119,enteric fermentation methane contained within enclosure air 120 isexposed to methane-utilizing microorganisms 121 and growth-culturemedium 122, causing methane-utilizing microorganisms 121 to grow andreproduce using enteric fermentation methane as a source of carbonand/or energy. The process continues when, after a certain amount oftime (in this embodiment approximately 7 days) it is determined thatmethane-utilizing microorganisms 121 within mutual-exposure means 119are no longer growing at optimal rates, and the microorganism growthprocess is augmented by removing portions of growth-culture medium 122and methane-utilizing microorganisms 121 from mutual-exposure means 119and adding new portions of growth-culture medium 122 and/ormethane-utilizing microorganisms 121. In such a manner, entericfermentation methane is continually used as a source of carbon and/orenergy for the continuous growth and harvesting of methane-utilizingmicroorganisms. Finally, methane-utilizing microorganisms 121, havingbeen grown in mutual-exposure means 119 using enteric fermentationmethane as a source of carbon and/or energy, are removed frommutual-exposure means 119 and harvested as useful biomass. Such biomasscan be processed and sold as a range of useful biomass-based products.

In one preferred embodiment, as described earlier, ventilation means 113are employed to move 10 cubic feet of enclosure air 120 out of airoutlet 117 each minute, such that fresh air enters into enclosure means115 at the same rate, and enclosure air 120 is cooled by the air coolingmeans described earlier. As described, a dairy cow producesapproximately 150 kilograms of methane per year, which correlates to theproduction of approximately 0.4 liters per minute of entericfermentation methane. Thus, by enclosing ruminant animal 114 withenclosure means 115 and employing ventilation means 113, theconcentration of methane in enclosure air 120 conveyed intomutual-exposure means is at least 0.1% methane by volume, or 1000 partsper million. By decreasing or increasing ventilation rates, theconcentration of methane in enclosure air 120 increases or decreasesaccordingly. Methane-utilizing microorganisms are able to grow andreproduce using methane as a source of carbon and/or energy in anenvironment wherein the concentration of methane-in-air is at least 1.7parts per million. Thus, methane-utilizing microorganisms 121 areenabled to grow and reproduce using enteric fermentation methane as anovel source of energy in one preferred embodiment.

Several embodiments of the present invention pertain to the utilizationof enteric fermentation as a novel source of energy for the productionof methane-based goods in a confined methane-consumption apparatusexisting outside the digestive tract of a ruminant animal. There are anumber of potential methods that can be used to carry out a process inaccordance with embodiments of the invention. In particular, there are anumber of methods that can be utilized to capture enteric fermentationmethane with enclosure and ventilation means and mutually-expose entericfermentation methane and a methane-consumption means for the purpose ofcausing enteric fermentation methane to be utilized as a source ofcarbon and/or energy.

In some embodiments, such methods include, but are not limited to,providing methane-consumption means to convert enteric fermentationmethane into heat and/or electricity. It is known that the utilizationof methane is possible at methane-in-air volumetric concentrations downto 0.1% methane-in-air, specifically by catalytic and thermalflow-reversal reactors, and systems such as these could be used as ameans to utilize enteric fermentation as a viable, low-concentrationsource of energy in accordance with the invention. Specifically,microturbines, fuel cells, reverse-flow reactors and other means capableof utilizing methane at low concentrations can be used as amethane-consumption means in accordance with the invention, allowingenclosure air to be used in an unadulterated state as viable feedstockfuel. Gas concentrators that increase methane-in-air concentrations ofexhaust gas could also be employed to increase methane concentrations tolevels more suitable for use by a range of methane-consumption means.Thus, although one preferred embodiment details the use ofmethane-utilizing microorganism as a preferred methane-consumptionmeans, in another embodiment, any number of methane-consumption meansmay be employed in accordance with embodiments of the invention toconvert enteric fermentation methane into useful products such as heatand/or electricity.

In some embodiments, such methods also include the combined use ofnon-enteric fermentation methane and enteric fermentation methane in orby a methane-consumption means, such that enteric fermentation methanecan be partially used to drive one or more methane-consumption means,such as fuel cells, turbines, microturbines, methane-utilizingmicroorganisms, and other methane-based systems. Such alternativesources of supplemental methane might include: methane from agriculturalmanure digesters, agricultural manure holding structures, landfills,coal mines, wastewater treatment facilities, and/or natural gas.

In some embodiments, such methods further include the utilization of achemical-based methane-consumption means to use enteric fermentationmethane as a source of carbon and/or energy. Specifically, a number ofmethods are well known to convert methane into industrial feedstockproducts, such as methanol, through the mutual exposure of methane andvarious chemicals under a variety of conditions. Suitable chemicalprocessing methods of this nature could be applied to entericfermentation methane in accordance with the principles of the invention,especially through the combined use of enteric fermentation methane andalternative sources of methane, as enumerated above, to increase theyields, viability, and efficiency of the process.

In some embodiments, such methods also include using methane-utilizingmicroorganisms to simultaneously reduce both ammonia and methaneemissions from ruminant animal feedlots. In one preferred embodiment,enclosure air 120 will likely contain varying amounts of ammonia gas. Itis well known that contacting ammonia gas with liquid water changesammonia gas into aqueous ammonium, as would occur in mutual-exposuremeans 119 of one preferred embodiment listed above when enclosure gas120 is contacted with growth-culture medium 122. It is well known thatmethane-utilizing microorganisms utilize ammonium in water as a sourceof nitrogen for growth. Thus, one embodiment of the invention mayinclude the use of unadulterated enteric fermentation to not onlyproduce methane-utilizing microorganisms, but to simultaneously reducefeedlot ammonia emissions as well.

In some embodiments, such methods also include using enclosure meansand/or methane-consumption means, as detailed above, to reduce dust orsuspended particles emissions associated with ruminant animals. In orderto increase the efficiency of a methane-driven system as detailed above,a filter may be used to prevent dust and/or other airborne particlesfrom entering into mutual exposure means 119. Thus, a process employedin accordance with the invention may be used to reduce entericfermentation methane emissions while simultaneously reducing emissionsof suspended particles typically associated with ruminant animals.

In some embodiments, such methods further include providing means toconvey enclosure air 120 from areas enclosed by enclosure means 115where enteric fermentation methane is known to accumulate, such as nearfeeding tracts, roof lines, or other potential methane accumulationareas. Such methods also include situating a means for mutual-exposurecontaining a methane-consumption means inside of an area enclosed anenclosure means, wherein means may or may not be provided tocontinuously or mechanically direct enclosure air to contact amethane-consumption system, but in either case causing entericfermentation to be utilized as a source of energy for the production ofmethane-based goods.

The above-detailed embodiment pertains to the use of entericfermentation methane as a novel source of energy for the production ofmethane-utilizing microorganisms in a confined growth-and-harvestapparatus existing outside of the digestive tract of a ruminant animal.There are a number of potential methods that can be used to carry out aprocess in accordance with the invention. In particular, there are anumber of methods that can be utilized to mutually-expose entericfermentation methane, methane-utilizing microorganisms, and amicroorganism growth-culture medium for the purpose of causingmethane-utilizing microorganisms to grow using enteric fermentationmethane as a source of carbon and/or energy.

In some embodiments, such methods include confining a ruminant animal toa site provided with means to funnel, convey, and/or direct entericfermentation methane into an apparatus whereby such enteric fermentationmethane is used to grow methane-utilizing microorganisms in a confinedapparatus, and whereby the means used to carry out this process areeither partially situated on a ruminant animal or not at all situated ona ruminant animal.

In some embodiments, such methods also include providing means to conveyenteric fermentation methane from a site where ruminant animals areknown to frequent, such as feeding or sleeping areas, to a means for themutual-exposure of enteric fermentation methane, methane-utilizingmicroorganisms, and a microorganism growth-culture medium, wherebymethane-utilizing microorganisms grow using enteric fermentation methaneas a source of carbon and/or energy in an apparatus existing outside ofthe digestive tract of a ruminant animal.

In some embodiments, such methods also include causing methane-utilizingmicroorganisms to grow by mutually-exposing enteric fermentationmethane, methane-utilizing microorganisms, and a microorganismgrowth-culture medium in a confined apparatus, wherein some or all ofthe methane-utilizing microorganisms are genetically-engineered.

In some embodiments, such methods also include growing methane-utilizingmicroorganisms using enteric fermentation methane as a source of carbonand/or energy for such growth, whereby the means used to carry out theprocess are powered by solar, wind, methane-based, or other suitableform of power different from the source of power—battery power—mentionedin the above detailed description.

There are also a number of methods in accordance with severalembodiments of the invention that can be utilized to mutually-exposeenteric fermentation methane, methane-utilizing microorganisms, and amicroorganism growth-culture medium for the purpose of causingmethane-consumption systems to operate using enteric fermentationmethane as a source of carbon and/or energy.

In some embodiments, such methods also include collecting, storing,and/or transporting ruminant animal methane for later use in a processcarried out in accordance with the invention.

In any case, the detailed description of one preferred method ofcarrying out a process in accordance with the invention should serveforemost as an elucidation of the practical and technologicalfeasibility of carrying out the invention, rather than as a limitationof the process of the invention itself.

As described herein, several embodiments of the present inventionprovide a novel process for the utilization of methane emitted byruminant animals. Preferred embodiments of the invention provide areparticularly advantageous because they:

(i) convert a previously wasted form of energy into a usefulend-product,

(ii) convert an environmentally-destructive greenhouse gas into a usefulend-product,

(iii) provide a direct economic incentive for a ruminant animal methaneemissions reduction effort,

(iv) reduce atmospheric ruminant animal methane emissions withoutaltering the chemical or microbial make-up of the digestive tract ofruminant animals,

(v) reduce atmospheric ruminant animal methane emissions withoutrequiring ruminant animals to alter their normal/natural behaviorpatterns, including sleeping and nutrient-consumption,

(vi) reduce atmospheric ruminant animal methane emissions withoutrequiring feed reformulations, selective breeding activities, orchemical or microbial modifications to the digestive systems of ruminantanimals,

(vii) utilize as a source of energy a material never previouslyconsidered a viable source of energy, and/or

(viii) have the potential, especially if used widely, to significantlyreduce ruminant animal methane emissions.

While the above description of preferred methods of carrying out aprocess in accordance with embodiments of the invention contains manyspecificities, these should not be construed as limitations on the scopeof the invention. As stated, there are a number of ways to carry out aprocess in accordance with invention. Accordingly, the scope of theinvention should be determined not by the preferred method described,but by the appended claims and their legal equivalents.

1. A method for oxidizing methane using a source of oxygen and theenteric fermentation methane produced by one or more ruminant animals asa source of carbon and/or energy, comprising: a. providing one or moreruminant animals contained in an enclosure; b. providing a first gascomprising enteric fermentation-derived methane gas that has beenemitted by and collected directly from said animals; c. providing asecond gas comprising air that has been combined with said first gas insaid enclosure, wherein said second gas comprises oxygen and wherein theconcentration of said enteric fermentation-derived methane in saidcombination of first and second gases is between 1.7 ppm and 1000 ppm;d. providing a culture of at least one methanotrophic microorganism,wherein said microorganism oxidizes methane to methanol, water, and/orcarbon dioxide, wherein said microorganism is unable to utilize saidfirst gas as a sole source of methane; e. providing a third gascomprising methane, wherein the amount of methane in said third gas issufficient to support the growth of said at least one microorganism whenfed to said microorganism; f. introducing a combination of said first,second and third gases into a culture chamber comprising said at leastone methanotrophic microorganism thereby oxidizing a portion of saidmethane in both said first and third gases to methanol, water, and/orcarbon dioxide.
 2. The method of claim 1, wherein an air conveyor isprovided to direct, move, and/or convey said second gas, wherein the airconveyor can be used to contact said second gas with said third gasand/or said microorganism.
 3. The method of claim 1, wherein saidmicroorganism utilizes methane monooxygenase to oxidize methane tointracellular methanol and/or carbon dioxide, and subsequently utilizessaid intracellular methanol and/or carbon dioxide for cellularmetabolism.
 4. The method of claim 1, wherein said second gas comprisesair, dust, non-methane organic matter, ammonia, gases, flies,particulate matter, and/or airborne matter fully or partially containedby said enclosure.
 5. The method of claim 1, wherein said second gas iscontacted with said microorganism to function as an oxygen source forsaid microorganism that reduces environmental enteric fermentationmethane emissions.
 6. The method of claim 1, wherein the flow rate ofsaid second gas conveyed through said enclosure is reduced to increasethe concentration of said methane within said enclosure, or wherein theflow rate of said second gas conveyed by said conveyor through saidenclosure is increased to reduce the concentration of said methanewithin said enclosure.
 7. The method of claim 1, wherein the temperatureand flow rate of said air within said enclosure are simultaneouslycontrolled to optimize the health of said ruminant animals within saidenclosure and the concentration of said oxygen and/or methane.